As a writer, the only time you should break the rules is when you know the rules beforehand.
Fortunately, in writing, there are no rules. Which is why you must be extra careful before you go around breaking them and drawing attention to yourself.
I know. Sounds screwy and somewhat zen-like. But there’s a lot of truth in it. Many classics have withstood the test of time because they are stories which, in one form or another, broke rules. These can be rules of grammar, pacing, POV, format, a lot of different elements. You can name just as many as I can off the top of your head, probably more. Novels like Lolita, Tropic of Cancer, Dracula, Blood Meridian, Moby-Dick, 1984 and on and on.
But you have to know what the basic rules are before you go around breaking them. That means you have to learn your craft inside and out. You have to do your homework and you have to keep your mouth shut and listen when professionals are talking about writing. Because you know what? You can tell instead of show…but only if you know how to show instead of tell first. You can mix POV in a scene. But only if you know and understand why it’s normally not done in the first place.
There are lots of others like this. You can break all the rules because writing is not a protocol exercise. It’s an organic creative process. Because it is organic it has the leeway already built in so you can leaven your imagination into it and make something truly memorable, truly artistic.
I am a big believer in breaking rules. You should be, too. But learn what they are first and then when you do break them it won’t be because you’re an amateur, it will be because you are empowered. :)